System level information for discontinuous reception, cell reselection and rach

ABSTRACT

A wireless transmit/receive unit is configured to receive system level information, including discontinuous reception (DRX) information, cell selection information, and RACH information. The system level information is received as defined parameters assigned to system information blocks or signaled through dedicated RRC signaling.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. provisional application No.60/953,816 filed on Aug. 3, 2007, which is incorporated by reference asif fully set forth.

FIELD OF INVENTION

The present application is related to wireless communications.

BACKGROUND

The Third Generation Partnership Project (3GPP) has initiated the LongTerm Evolution (LTE) program to bring new technology, new networkarchitecture, new configurations and new applications and services towireless cellular networks in order to provide improved spectralefficiency and faster user experiences.

In order for a wireless transmit receive unit (WTRU) to perform variousprocedures related to sleep, monitoring the paging cycles, cellreselection or using a random access channel (RACH), a network wouldtypically signal a number of parameters to the WTRU in systeminformation messages. Some of these parameters can also be used when theWTRU is in an active state, including, but not limited to, reducedneighbor cell lists, measurement reporting and handover parameters.There is a need to put all necessary parameters together and group theminto system information messages for use by the WTRU in procedures andmethods for sleep, reselection or RACH procedures.

Within a core network (CN) domain system information, information for adiscontinuous reception (DRX) would typically be signaled to a WTRU inidle mode in an information element (IE) (e.g.,CN_DRX_cycle_length_coefficient). However, DRX exists in active mode aswell as idle mode. Therefore, it would be beneficial to signal a DRXcycle length for the active mode.

When a WTRU is camped on a cell, it regularly searches for a better cellaccording to a set of criteria. If a better cell is found, that cell isselected. In an LTE system with only two states LTE_Idle and LTE_active,the WTRU can perform cell reselection only in the LTE_Idle state. TheWTRU uses parameters broadcasted from the system, including, but notlimited to the following parameters that are transmitted in a systeminformation block (SIB), such as SIB 3, SIB 4 and/or SIB 11:

-   -   Q_(hyst1s): Used in ranking serving cell based on RSCP.    -   Q_(hyst2s): Used in ranking serving cell based on Ec/Io.    -   Q_(qualmin): Minimum required quality measure based on Ec/Io.    -   Q_(rxlevmin): Minimum required quality measure based on a        received signal power measurement (e.g., received signal code        power (RSCP)).    -   Delta_(Qrxlevmin): (conditional on value Delta) If present, the        actual value of Q_(rxlevmin)+Delta_(Qrxlevmin).    -   UE_TXPWR_MAX_RACH: Maximum allowed uplink (UL) TX power    -   S_(intrasrch) (optional): Measure intra-frequency neighbor cells        when S_(quat)≦S_(intrasearch), where Squal is based on measured        signal to interference ration of a corresponding cell measured        by the WTRU minus Q_(qualmin).    -   S_(intersrch) (optional): Measure inter-frequency neighbor cells        when S_(qual)≦S_(intersearch).    -   S_(searchHCS) (optional): Measure inter-Hierarchal Cell        Structure (HCS)/inter-frequency neighbor cells when        S_(qual)≦S_(searchHCS).    -   S_(HCS,RAT) (optional): Measure inter-Hierarchal Cell Structure        (HCS)/RAT neighbor cells when S_(qual)≦S_(HCS,RAT).    -   S_(limit,SearchRAT) (optional): This threshold is used in the        measurement rules for cell reselection when HCS is used. It        specifies the RAT specific threshold (in dB) in the serving UTRA        cell above which the UE may choose to not perform any inter-RAT        measurements in RAT “m”.

SUMMARY

A wireless transmit/receive unit (WTRU) is configured to receive systemlevel information, such as discontinuous reception (DRX) information,cell reselection information and random access channel (RACH)information, in the form of system information blocks (SIBs) ordedicated radio resource control (RRC) message signaling. The WTRUautonomously processes the received parameters and alters its behaviorwith respect to sleep mode, cell reselection and using RACH signatures.

BRIEF DESCRIPTION OF THE DRAWING

A more detailed understanding may be had from the following description,given by way of example in conjunction with the accompanying drawingswherein:

FIG. 1 shows a discontinuous reception (DRX) cycle; and

FIG. 2 shows a protocol layer stack configuration for a wirelesstransmit/receive unit receiving system level information from an evolvedNode-B.

DETAILED DESCRIPTION

When referred to hereafter, the terminology “wireless transmit/receiveunit (WTRU)” includes but is not limited to a user equipment (UE), amobile station, a fixed or mobile subscriber unit, a pager, a cellulartelephone, a personal digital assistant (PDA), a computer, or any othertype of user device capable of operating in a wireless environment. Whenreferred to hereafter, the terminology “base station” includes but isnot limited to a Node-B, a site controller, an access point (AP), or anyother type of interfacing device capable of operating in a wirelessenvironment.

FIG. 1 shows a WTRU 101 comprising a protocol layer stack that includesthe following layers: radio resource control RRC 102, radio link control(RLC) 103, medium access control (MAC) 104, packet data convergenceprotocol (PDCP) 105, and a physical (PHY) layer 106. These layerentities may be implemented as a single processor or separateprocessors. The WTRU 101 receives system level information from anevolved NodeB (eNB) 121 in a wireless downlink signal 111. The systemlevel information may be defined in units of system information blocks(SIBs) and parameters within each of the SIBs may be used by the WTRU101 for various processes which will be explained in further detail. Theparameters may be defined into groups of information elements (IEs),which can be processed, for example, by the RRC 102 for controllingoperation of the other layer entities. One example includes the RRC 102receiving DRX parameters and then instructing the PHY 106 to sleepduring the designated DRX cycle parameters. In general, the WTRU 101receives and processes the system level information, and autonomouslyperforms the corresponding operations.

In a first example of defining SIBs with system level information, asystem information block 1 (SIB1) may be defined by information elementsand related information as shown in Table 1. Each of the IEs shown inTable 1, as well as all tables shown herein, may be defined and providedto the WTRU 101 on a need basis that includes, but is not limited to,the following: mandatory, mandatory with a default value available,conditional on a value, or optional.

TABLE 1 Semantics Group Name Information Element Type and referencedescription CN CN common GSM- NAS system information MAP NAS systeminformation (GSM- elements information MAP) >Domain system Domain systeminformation information (for PS domain) WTRU WTRU Timers and WTRU Timersand The WTRU information constants in idle constants in idle modebehaviour is mode unspecified if this IE is absent. WTRU Timers and WTRUTimers and constants in active constants in active (connected) mode(connected) mode

As shown in Table 1, the core network (CN) IEs include common GSM-mobileapplication part (MAP) non-access stratum (NAS) system information anddomain system information for the packet switched (PS) domain. These IEsinform the WTRU 101 about the serving CN and domain system. The LTEnetwork operates only in a packet switched (PS) domain. Therefore, thereis no need to maintain any other domain information. Only PS domaininformation is required to be signaled.

In the LTE specification, DRX operates in both explicit and implicitmodes. DRX parameters may be signaled by two IEs that can carry specificDRX parameters for each mode of operation. The IE can carry both DRXexplicit mode parameters and DRX implicit mode parameters. These IEs canbe signaled with the domain system information or may be transmittedwith another message, such as a RRC_Connection_Command message forexample.

FIG. 2 shows a set of sequential DRX signal cycles, in which the WTRU101 has an active period and a sleep period for the remainder of the DRXcycle, allowing the WTRU 101 to reduce battery consumption. The variableDRX parameters for defining the DRX cycle are the DRX cycle start time,the active period length and the DRX cycle length. For LTE idle mode,the WTRU 101 monitors system paging only during the active period. ForLTE active mode, or RRC connected mode, the WTRU 101 only receives dataduring the active period. Adjustments to DRX parameters may becomenecessary, for example, to overcome poor channel conditions or toincrease the amount of data reception upon the transition from LTE idlemode to LTE active mode. For DRX configuration, if the WTRU 101 is inLTE active mode, the network can signal the same or different parametersas for the WTRU 101 in LTE idle mode. Also, the network may group theparameters and identify the group with a DRX profile identifier (ID).This may enable the network to signal the WTRU 101 to use a particularprofile. The signaling received by the WTRU 101 may be through RRC orMAC signaling and may provide the DRX cycle start time, as shown in FIG.2.

Table 2 shows an example of LTE idle mode and LTE active mode DRXconfiguration IEs and associated parameters for this embodiment, forwhich the WTRU 101 is configured to receive and process. An IE for CNDRX cycle period length in LTE idle mode indicates the length of theentire DRX cycle for the WTRU 101 to use while receiving paging in idlemode. An IE for LTE active mode parameters indicates to the WTRU 101whether LTE active mode parameters are to be the same as the idle modeparameters, or different than the idle mode parameters. If different,the network may then specify a different set of active mode parameters.In order to allow the WTRU 101 to synchronize to the DRX cycle, an IEfor DRX cycle start time is defined. In this example, the cell systemframe number (SFN) is used as a reference for the DRX cycle start time.A choice IE, Choice Signaling Method, is defined by the network andreceived by the WTRU 101 to indicate the type of DRX signaling methodbeing employed, which is either explicit type or implicit type,explained later in further detail with respect to Tables 3 and 4.

TABLE 2 LTE Active mode and LTE Idle mode Information Type andElement/Group name reference Semantics description CN DRX cycle periodInteger(1 . . . x) Refers to the length of the entire DRX cycle lengthIn LTE Idle Mode in WTRU Idle mode for paging. LTE_Active Mode DRXEnumerated Network specifies whether the Active mode parameters (same asIdle, DRX parameters are the same as or different) different than theIdle mode parameters. If specified that the Active mode DRX parametersare different, network may specify a different set of values for theActive mode parameters. >DRX Cycle Start Time Integer Configured DRXCycle in LTE_Active (0 . . . 4093) starts on an SFN >CHOICE Signalingmethod >> Explicit >>> Explicit DRX Explicit DRX ConfigurationConfiguration Info (Table 3) >> Implicit >>> Implicit DRX Implicit DRXConfiguration Configuration Info (Table 4)

Table 3 shows a summary of an exemplary configuration for informationelements used in explicit DRX signaling. As a choice IE, the DRXconfiguration mode may indicate either a Full Configuration or aPredefined Configuration mode. For the Full Configuration mode, thenetwork provides all of the DRX parameters to the WTRU 101. In thePredefined Configuration mode, the WTRU 101 uses default DRX parametersthat are predefined by the network. The DRX profile ID informationelement can be used for defining different DRX profiles which can beused for changing the DRX lengths and other parameters during variousprocedures, including 3GPP to non-3GPP handovers.

TABLE 3 Explicit DRX Information Element/ Type and Group Name referenceSemantics description Choice DRX Configuration Mode > FullConfiguration >>DRX Cycle length in Integer (1 . . . X) DRX Cycle Lengthin unit of the LTE Active mode number of system frames >>Active periodlength in Integer (1 . . . 10) Active duty cycle length in unit of LTEActive mode sub-frames >>Active period position Enumerated Indicatingthe active duty period (first, last) is in the beginning or the end ofthe cycle >> Active period start sub- Integer (1, . . . , 9) Thesub-frame number at which frame the active period starts in its firstframe, if it is not on the frame boundary > Predefined Configuration >>DRX profile ID Integer (1 . . . X) Network signals a profile ID with theset of already defined parameters when it wants the WTRU to use apredefined configuration

Table 4 shows a summary of an exemplary configuration for informationelements used in implicit DRX signaling. As shown, the IE for ImplicitDRX State and Transition List may have multiple instances in thesignaling to the WTRU 101, one per maximum number of DRX states. Similarto the Explicit DRX explained above, there is a choice IE for DRXconfiguration mode, for either a Predefined configuration or a FullConfiguration. Under a Full configuration mode, trigger mechanism IEsTrigger-UP-1, Trigger-Down-1 and Trigger-Down-2 are defined. TheTrigger-UP-1 IE indicates the WTRU 101 is to move to the next upperlevel DRX state (i.e., a longer DRX cycle). The Trigger-Down-1 IE is atrigger mechanism for the WTRU 101 to move the next lower level DRXstate (i.e., a shorter DRX cycle). For the Trigger-Down-2 IE, the WTRU101 receives a trigger mechanism to move to the shortest DRX cycle,Level-1. For each of these trigger IEs, a choice IE for TriggeringMechanism includes either a timer or a measurement event, as summarizedin Table 5. If a timer trigger mechanism is applied, a timer value IE,Implicit-DRX-triggering-timer, may be included. For a measurement eventtrigger, an Implicit DRX triggering event IE may be included, based ontraffic volume and/or inter-frequency, intra-frequency, inter-RAT,intra-RAT measurement events, and an IE for threshold value to be usedfor the measurement event may also be included.

TABLE 4 Implicit DRX Information Element/Group name Multiple Type andreference Semantics description Initial DRX state Implicit DRX Time inseconds Transition configured life span Implicit DRX State <1, . . . ,and Transition List maxDRXstates> CHOICE DRX- Config-Mode > PredefinedConfiguration CN DRX profile ID Integer (1 . . . X) Network could signala profile ID with each of the parameters and so the network could signalthe WTRU to use a particular DRX profile ID when it wants the WTRU touse a predefined configuration > Full Configuration >>DRX Cycle IntegerLength >>Trigger-UP-1 Trigger Mechanism (Table To next upper level DRX5) State >>Trigger-Down-1 Trigger Mechanism (Table To next lower levelDRX 5) state >>Trigger-Down-2 Trigger Mechanism (Table To Level-1(shortest DRX 5) cycle) trigger >>>DRX Cycle Integer DRX Cycle Length inunit length in LTE (1 . . . X) of the number of system Active modeframes >>>Active period Integer Active duty cycle length in length inLTE (1 . . . 10) unit of sub-frames Active mode >>>Active periodEnumerated Indicating the active duty position (first, last) period isin the beginning or the end of the cycle [this may not be needed if wehave the system define that the active period always starts in the firstframe of the DRX cycle] >>> Active period Integer (1, . . . , Thesub-frame number at start sub-frame 9) which the active period starts inits first frame, if it is not on the frame boundary

TABLE 5 Triggering mechanisms Information Element/ Type and Group namereference Semantics description CHOICE triggering- mechanism >Timer >>Implicit-DRX- Integer (10, 20, Timer value in unit oftriggering-timer 50, 100, 200, 500, milli-seconds 1000, . . . X) >Measurement-event Integer (1 . . . 10) >>Implicit-DRX- MeasurementTraffic volume triggering-event Event ID measurement events &inter/intra F/R measurement events >> Event-associated threshold value

Additional IEs provided to the WTRU 101 for defining the DRX cycle mayinclude DRX Cycle length, the active period length, the active periodposition and the active period start subframe. For the DRX cycle lengthIE, the parameter indicates the DRX cycle length for LTE active mode inunits of system frames and indicating if this DRX parameter is differentthan the LTE idle mode parameter. The active period length IE indicatesthe active duty cycle length in sub-frames for LTE active mode, andwhether the parameter is different than the LTE idle mode parameter. Theactive period position IE indicates whether the active duty period is atthe beginning or at the end of the DRX cycle whether the parameter isdifferent than the LTE idle mode parameter. If the active period doesnot start at a frame boundary, then the active period start sub-frame IEprovides the sub-frame number at which the active period starts.

In another embodiment, parameters for cell selection and reselection aredefined and transmitted in a SIB 3, for example, or one of the otherSIBs defined in the 3GPP specifications. Upon receiving and processingthese parameters, the WTRU 101 autonomously performs cellselection/reselection operations. Tables 6 and 7 show a summary of anexample configuration of IEs containing cell selection and reselectionparameters.

TABLE 6 Cell Selection and Reselection Information Type andElement/Group name reference Semantics description SIB4 IndicatorBoolean TRUE indicates that SIB4 is broadcast in the cell. UTRANmobility information elements Cell identity Cell identity Cell selectionand re- Cell selection selection info and re-selection info for SIB3/4Cell Access Restriction Cell Access Restriction Access RestrictionAccess This IE specifies the Access Restriction Parameters For PLMN OfRestriction Parameters for WTRUs which have chosen MIB Parameters thePLMN in the IE “PLMN identity” of the Master Information Block. DomainSpecific Access Restriction For Shared Network >CHOICE barringrepresentation >> Access Restriction Parameter List >>> AccessRestriction PS Domain This IE specifies the Access RestrictionParameters For Specific Access Parameters for WTRUs which have chosenOperator1 Restriction the first PLMN in the IE “multiplePLMNs”Parameters in the IE “Multiple PLMN List” of the Master InformationBlock. >>> Access Restriction PS Domain This IE specifies the AccessRestriction Parameters For Specific Access Parameters for WTRUs whichhave chosen Operator2 Restriction the second PLMN in the IE Parameters“multiplePLMNs” in the IE “Multiple PLMN List” of the Master InformationBlock. >>> Access Restriction PS Domain This IE specifies the AccessRestriction Parameters For Specific Access Parameters for WTRUs whichhave chosen Operator3 Restriction the third PLMN in the IE Parameters“multiplePLMNs” in the IE “Multiple PLMN List” of the Master InformationBlock. >>> Access Restriction PS Domain This IE specifies AccessRestriction Parameters For Specific Access Parameters for WTRUs whichhave chosen Operator4 Restriction the fourth PLMN in the IE Parameters“multiplePLMNs” in the IE “Multiple PLMN List” of the Master InformationBlock. >>> Access Restriction PS Domain This IE specifies the AccessRestriction Parameters For Specific Access Parameters for WTRUs whichhave chosen Operator5 Restriction the fifth PLMN in the IE“multiplePLMNs” Parameters in the IE “Multiple PLMN List” of the MasterInformation Block. >> Access Restriction Parameters For All >>> AccessRestriction PS Domain This IE specifies the common Access ParametersSpecific Access Restriction Parameters applied to all Restriction PLMNsin the IE “multiplePLMNs” in the Parameters IE “Multiple PLMN List” ofthe Master Information Block.

As seen in Table 6, for a choice IE for barring representation, eitheran IE “Access restriction parameter list” IE or an “Access restrictionparameter for all” IE is selected. If the “Access restriction parameterlist” IE is applied, then multiple IEs are available for specifyingaccess restriction parameters for WTRUs assigned to a respective publicland mobile network (PLMN), which is identified in an IE “multiplePLMNs”in the IE “Multiple PLMN List” in the master information block (MIB).When the “Alternative access restriction parameters for all” IE ischosen, then a set of common access restriction parameters is indicatedto the WTRU 101, which is applied to all PLMNs in the IE “multiplePLMNs”. As there is one PS domain, the parameters for the CS domain arenot specified.

As shown in Table 7, the WTRU 101 may receive an IE for Cell selectionand reselection quality measure based on RSRP and/or RSRQ, an IE forradio access technology (RAT) of the candidate cell for selection, and aTreslection IE that indicates the reselection time parameter. Withrespect to the Qhyst IE, the WTRU 101 may receive the following scalingfactors: an IE that indicates a Speed dependent scaling factor, anInter-frequency Speed dependent scaling factor, and an Inter RAT Speeddependent scaling factor. A Neighbor cell blacklist IE may be receivedby the WTRU 101 to indicate a list of neighbor cells forbidden by thenetwork for reselection.

Before the WTRU 101 makes received signal measurements for cellselection/reselection, the WTRU 101 may receive and process an UTRAN_minIE or GERAN_Min which indicate the minimum signal power for a UTRAN orGERAN cell, respectively. The IEs Qoffset1 and Qoffset2 may be receivedby the WTRU 101 to indicate biasing cell measurements

TABLE 7 Cell selection and reselection Information Element/ Group nameMultiple Type and reference Semantics description Cell selection andEnumerated Choice of measurement (RSRP or reselection quality (RSRP,RSRQ) RSRQ) to use as quality measure Q measure for FDD cells. This IEis also sent to the WTRU in SIB11/12. Both occurrences of the IE shouldbe set to the same value. CHOICE mode >FDD >>S_(intrasearch) Integer(−32 . . . 20 by If a negative value is received the step of 2) WTRUconsiders the value to be 0. [dB] >>S_(intersearch) Integer (−32 . . .20 by If a negative value is received the step of 2) WTRU considers thevalue to be 0. [dB] >>S_(searchHCS) Integer (−105 . . . 91 by If anegative value is received the step of 2) WTRU considers the value to be0. [dB] >>RAT List 1 to <maxOtherRAT> >>>RAT identifier Enumerated (GSM,CDMA2000, UTRAN, any other non 3GPP RAT like WiFi, WiMAx, UMAetc) >>QSearch_TH Integer (−32 . . . 20 by In case the value 20 isreceived the step of 2) WTRU considers this IE as if it was absent. If anegative value is received the WTRU considers the value to be 0. [dB]>>>S_(HCS,RAT) Integer (−105 . . . 91 by If a negative value is receivedthe step of 2) WTRU considers the value to be 0. [dB]>>>S_(limit,SearchRAT) Integer (−32 . . . 20 by If a negative value isreceived the step of 2) WTRU considers the value to be 0.[dB] >>Qqualmin Integer (−24 . . . 0) RSRP, [dB] >>Qrxlevmin Integer(−115 . . . −25 RSRQ, [dBm] by step of 2) >> Delta_(Qrxlevmin)Integer(−4 . . . −2 by If present, the actual value of step of 2)Qrxlevmin = Qrxlevmin + Delta_(Qrxlevmin) >> TDD >>S_(intrasearch)Integer (−105 . . . 91 by If a negative value is received the step of 2)WTRU considers the value to be 0.[dB] >>S_(intersearch) Integer (−105 .. . 91 by If a negative value is received the step of 2) WTRU considersthe value to be 0.[dB] >>S_(searchHCS) Integer (−105 . . . 91 by If anegative value is received the step of 2) WTRU considers the value to be0.[dB] >>RAT List 1 to <maxOther- RAT> >>S_(search,RAT) Integer (−105 .. . 91 by In case the value 91 is received the step of 2) WTRU considersthis IE as if it was absent. If a negative value is received the WTRUconsiders the value to be 0. [dB] >>S_(HCS,RAT) Integer (−105 . . . 91by If a negative value is received the step of 2) WTRU considers thevalue to be 0. [dB] >>S_(limit,SearchRAT) Integer (−105 . . . 91 by If anegative value is received the step of 2) WTRU considers the value to be0. [dB] >>Qrxlevmin Integer (−115 . . . −25 by RSCP, [dBm] step of 2) >>Delta_(Qrxlevmin) Integer (−4 . . . −2 by step If present, the actualvalue of of 2) Qrxlevmin = Qrxlevmin + Delta_(Qrxlevmin) Qhyst1_(s)Integer (0 . . . 40 by step [dB] of 2) Qhyst2_(s) Integer (0 . . . 40 bystep Default value i sQhyst1_(s) of 2) [dB] Treselection_(s) Integer (0. . . 31) [s] Speed dependent Real (0 . . . 1 by step of This IE is usedby the WTRU in high ScalingFactor for 0.1) mobility state as scalingfactor for Treselection Treselection_(s) Inter-frequency Real (1 . . .4.75 by step of 0.25) If present, it is used by the WTRU asScalingFactor for scaling factor for Treselection_(s) for Treselectioninter-frequency cell reselection evaluation ScalingFactor for of 0.25)as scaling factor for Treselection_(s) Treselection for inter-RAT cellreselection evaluation Speed dependent Real (0 . . . 1 by step of Ifpresent, it is used by the WTRU Scaling factor for 0.1) as scalingfactor for Qhyst for Qhyst inter-RAT cell reselection evaluationInter-frequency Real (1 . . . 4.75 by step If present, it is used by theWTRU Speed dependent of 0.25) as scaling factor for Qhyst_(s) forScaling factor for inter-RAT cell reselection Qhyst evaluation Inter-RATSpeed Real (1 . . . 4.75 by step If present, it is used by the WTRUdependent Scaling of 0.25) as scaling factor for Qhyst for factor forQhyst inter-RAT cell reselection evaluation Neighbour cellInteger(neighbour Network can specify the list of cells blacklist cellIDs) it does not want the WTRU to reselect to if it so desiresNon-HCS_T_(CRmax) Enumerated (not [s] used, 30, 60, 120, Default valueis ‘not used’. 180, 240) Non-HCS_N_(CR) Integer (1 . . . 16) Defaultvalue = 8 Non- Enumerated (not [s] HCS_T_(CRmaxHyst) used, 10, 20, 30,40, 50, 60, 70) HCS Serving cell HCS Serving cell Informationinformation Maximum allowed Maximum allowed [dBm] UE_TXPWR_MAX_RACH ULTX power UL TX power UTRAN_Min/ Minimum value [dBm] above which theUTRAN cell should be to start measurements. GERAN_Min Minimum value[dBm] above which the GERAN cell should be to start measurements.Qoffset1 Value used for [dBm] biasing the cells for measurement Qoffset2Another offset [dBm] value used based on cell loading or any otherparameter Tmeas Number of seconds [s] between two consecutivemeasurements in Idle for Inter-RAT Priority of Inter- Priority of RATEnumerated (GSM, cdma2000, RAT reselection selection during the UTRAN,any other non 3GPP RAT Inter-RAT like WiFi, WiMAx, etc) reselectionprocess. WTRU would follow this list in order.

In another embodiment, system level information for a PHY random accesschannel (PRACH) is defined by parameters in IEs and included into an SIB5, or another 3GPP specified SIB, to be received and processed by theWTRU 101. Tables 8-10 show a summary of example configurations of suchIEs and related information.

As shown in Table 8, a PRACH system information IE may be included withmultiple instances from 1 to maxPRACH. A PRACH-info IE for RACHcomprises several IEs that are summarized in Table 9. A RACHnon-dedicated signature IE indicates dedicated and non-dedicatedsignatures allocated to the WTRU 101, and comprises several IEs that aresummarized in Table 10. A RACH Response Window IE informs the WTRU 101as to a number of sub-frames over which multiple RACH responses sent tothe WTRU 101 are to be received. A PHY downlink control channel (PDCCH)information IE, “PDCCH-Info”, provides PDCCH parameters for the PRACH tothe WTRU 101, comprising IEs summarized in Table 12. A routingarea-radio network temporary identification (RA-RNTI) List IE,comprising IEs summarized in Table 11, provides RNTI information to theWTRU 101 for the routing area.

TABLE 8 PRACH system information Type and Information element Multiplereference Semantics description PRACH system 1 . . . <maxPRACH>information >PRACH info PRACH info (for RACH), see Table 9 >CHOICEmode >>FDD >>>Primary CPICH Primary TX Default value is the value of“Primary TX power power Reference Symbol TX power” for the previousPRACH in the list. (The first occurrence is then mandatory) >>>Constantvalue Constant Default value is the value of “Constant value value” forthe previous PRACH in the list. (The first occurrence is thenmandatory) >>>PRACH power PRACH Default value is the value of “PRACHoffset power offset power offset” for the previous PRACH in the list.(The first occurrence is then mandatory) >>>RACH RACH Default value isthe value of “RACH transmission transmission transmission parameters”for the parameters parameters previous PRACH in the list. (The firstoccurrence is then mandatory) >>>RACH non- RACH non- Dedicated and Nondedicated dedicated-signature dedicated- signatures allocated to theWTRU signature parameters See Table 10 >>> RACH Response Integer (1, . .. , RACH window (in number of sub- Window 10) frames) over whichmultiple responses sent to the WTRU are received. >>>PDCCH Info PDCCHDefault value is the value of “PDCCH info See info” for the previousPRACH in the Table 12 list. (The first occurrence is then mandatory) >>>RA-RNTI List RA-RNTI Default value is the value of “RA-RNTI Info List”for the previous PRACH in the See Table list. 11 (The first occurrenceis then mandatory)

As shown in Table 9, WTRU 101 receives PRACH information parameters forfrequency division duplex (FDD) and time division duplex (TDD)operation. For FDD, the WTRU 101 may receive a PRACH frequency positionIE indicating an integer value within a range starting from the lowestfrequency edge of the carrier bandwidth. Alternatively, the integervalue may range between negative and positive values centered in themiddle of the carrier frequency. Additional parameters received by theWTRU 101 include a PRACH burst type IE (e.g., normal, extended orrepeated burst type) and a Channel Coding parameter IE for identifyingthe turbo code in use. For TDD, the WTRU 101 may receive a PRACH Framestructure type IE and a PRACH Burst Type IE to indicate, for example, anormal or extended burst type.

TABLE 9 PRACH information Information Element/Group Type and namereference Semantics description CHOICE mode >FDD >>PRACH FrequencyInteger (0, . . . , Resource Block number scale Position (on beginningRB 105) starts from the lowest frequency number of the PRACH) edge ofthe carrier bandwidth OR >>PRACH Frequency Integer (−52, RB number scalefor 105 RBs Position (on beginning RB . . . , 0, . . . +52) with centerin the middle of the number of the PRACH) carrier frequency >>PRACHBurst Type Enumerated (Normal, Extended, Repeated) >> Channel CodingInteger (0, . . . xx) Identification of the turbo codeParameter >>Preamble scrambling code Integer (0 . . . 15) Identificationof scrambling code number >>Puncturing Limit Real(0.40 . . . 1.00 bystep of 0.04) >TDD >>PRACH Frame Structure Enumerated (Type-1,Type-2) >>PRACH Burst Type Enumerated (Normal, Extended) >> TBD

As shown in Table 10, the WTRU 101 may receive a set of RACH parametersdefined according to a group G1 for dedicated RACH signatures, a groupG2 for consecutive or bit-mapped non-dedicated RACH signatures, or agroup G3 for small message consecutive or bit-mapped non-dedicated RACHsignatures. Each RACH channel typically has 64 random access signaturesof cyclical Z-C codes whose generation/derivation is specified in 3GPPStandards. For system information, the signatures can be identified bytheir indexes (0, . . . , 63).

When a random access signature group whose signatures are allconsecutive in terms of the signature index, it can be defined by[start-index-a, range]. The WTRU 101 then knows and selects thesignatures within the defined group since they are consecutive. Forexample, WTRU 101 receives the Available Dedicated Signatures G1 IE, theNumber of Signatures IE with a value 8, and a Begin Signature Index IEwith value 8, then WTRU 101 can derive that its RACH signature group is[8-15].

But if the random access signatures in a group is not consecutive, thenthe above described signature index mapping IE is replaced by thealternative bit-mapped signature index, shown in Table 10 as theSignature Map IE. For the bit-mapped signature mapping, the WTRU 101receives a bit string which indicates a set of available signatures inthe random access signature group according to a predefined signaturemap. The Signature map IE use a bitmap with 64 bits, or with a firststart-index-a, and a subsequent bitmap in a range.

TABLE 10 RACH Non-dedicated Preamble/signatures Type and InformationElement/Group name reference Semantics description CHOICE mode >FDDAvailable Dedicated Signatures G1 >>> Number of signatures Integer (0,consecutive signatures in the 4, 8, 16, 24) group >>> Begin SignatureIndex Integer (0, . . . , Index number of the first 63) signature,present only if the number of signatures of the group is notzero >>Available Non-dedicated Signatures G2 >>> Number of signaturesInteger (0, Number of consecutive signatures 4, 8, 16, 24, in the group32, 48, 64) >>> Begin Signature Index Integer (0, . . . , Index numberof the first 63) signature, present only if the number of signatures ofthe group is not zero OR If signatures not consecutive >>> Signature mapBit string Set bit positions in the map (64) indicate the indexes ofavailable signatures in the group >>Available Non-dedicated SignaturesG3 >>> Number of signatures Integer (0, Number of consecutive signatures4, 8, 16, 24, in the group 32, 48, 64) >>> Begin Signature Index Integer(0, . . . , Index number of the first 63) signature, present only if thenumber of signatures of the group is not zero OR If signatures notconsecutive [ >>> Signature map Bit string Set bit positions in the map(64) indicating the indexes of available signatures in the group

TABLE 11 RACH RA-RNTI Information Information Element/Group Type andSemantics name Multi reference description RACH RA-RNTI Info <1, . . . ,At least 2 for a maxRA- RACH, 3 or more RNTI for betterdecoding >RA-RNTI Code Bit String (12 or 16 or ?) >Burst Start Integer Aburst is a sub- subframe number (0, . . . , 9) frame >Next BurstDistance Integer N sub-frames, (4, . . . , 20) equivalent to the RACHresponse window size

TABLE 12 PDCCH Information Information Element/Group Type and Semanticsname Need reference description PDCCH Info MP >PDCCH Format MPEnumerated (0, 1, 2, 3) >PDCCH Scrambling OP Integer Index to the (0, .. . , x) scrambling code tree

Other than the SIBs mentioned above, the LTE network could also transmita SIB 16 message which could carry some configuration parameters thatthe WTRU 101 could read and use when entering the LTE system during ahandover from another RAT (3GPP or non-3GPP) to LTE. Alternatively, theLTE system could transmit a SIB 16 message or some other analogousdedicated RRC message which would carry parameters applicable for thenon 3GPP RAT during a handover from LTE to other RAT (3GPP or non-3GPP).Such a message could have been possibly conveyed to the LTE system justbefore the handover procedure. This SIB 16 could contain a combinationof parameters like some of the DRX parameters mentioned, some RACH andreselection parameters and any other physical layer parameters whichmight give the WTRU 101 some knowledge of the system.

Although features and elements are described above in particularcombinations, each feature or element can be used alone without theother features and elements or in various combinations with or withoutother features and elements. The methods or flow charts provided hereinmay be implemented in a computer program, software, or firmwareincorporated in a computer-readable storage medium for execution by ageneral purpose computer or a processor. Examples of computer-readablestorage mediums include a read only memory (ROM), a random access memory(RAM), a register, cache memory, semiconductor memory devices, magneticmedia such as internal hard disks and removable disks, magneto-opticalmedia, and optical media such as CD-ROM disks, and digital versatiledisks (DVDs).

Suitable processors include, by way of example, a general purposeprocessor, a special purpose processor, a conventional processor, adigital signal processor (DSP), a plurality of microprocessors, one ormore microprocessors in association with a DSP core, a controller, amicrocontroller, Application Specific Integrated Circuits (ASICs), FieldProgrammable Gate Arrays (FPGAs) circuits, any other type of integratedcircuit (IC), and/or a state machine.

A processor in association with software may be used to implement aradio frequency transceiver for use in a wireless transmit receive unit(WTRU), user equipment (UE), terminal, base station, radio networkcontroller (RNC), or any host computer. The WTRU may be used inconjunction with modules, implemented in hardware and/or software, suchas a camera, a video camera module, a videophone, a speakerphone, avibration device, a speaker, a microphone, a television transceiver, ahands free headset, a keyboard, a Bluetooth® module, a frequencymodulated (FM) radio unit, a liquid crystal display (LCD) display unit,an organic light-emitting diode (OLED) display unit, a digital musicplayer, a media player, a video game player module, an Internet browser,and/or any wireless local area network (WLAN) or Ultra Wide Band (UWB)module.

What is claimed is:
 1. A method of processing information for a wirelesstransmit/receive unit (WTRU), the method comprising: receiving theinformation as a plurality of parameters defined as information elements(IEs) for a physical random access channel (PRACH) operation of theWTRU; and processing the received parameters to perform PRACH operationsby the WTRU, the IEs including PRACH system information, the PRACHsystem information including a random access channel (RACH) responsewindow size and PRACH frequency position information, the RACH responsewindow size provided as a number of subframes, and one or more RACHresponses sent to the WTRU being received by the WTRU over the RACHresponse window.
 2. The method as in claim 1, wherein the PRACH systeminformation further comprises PDCCH information and RA-RNTI information.3. The method as in claim 1, wherein the PRACH system informationfurther comprises at least one of PRACH burst type information or achannel coding parameter.
 4. The method as in claim 1, wherein the PRACHsystem information further comprises at least one of a PRACH burst typeparameter or a PRACH frame structure parameter.
 5. The method as inclaim 1, wherein the IEs include RACH non-dedicated preamble andsignature information.
 6. The method as in claim 5, wherein the RACHnon-dedicated preamble and signature information includes at least oneof the following parameters: a number of signatures, a begin signatureindex, or a signature map.
 7. The method as in claim 1, wherein the IEsinclude RACH dedicated preamble and signature information.
 8. The methodas in claim 7, wherein the RACH dedicated preamble and signatureinformation includes at least one of the following parameters: a numberof signatures or a begin signature index.
 9. The method as in claim 2wherein the RA-RNTI information includes at least one of the followingparameters: a RA-RNTI code, a burst start sub-frame number or a nextburst distance.
 10. The method as in claim 2 wherein the PDCCHinformation includes at least one of the following parameters: a PDCCHformat or a PDCCH scrambling code.
 11. A wireless transmit/receive unit(WTRU) comprising: a receiver configured to receive information as aplurality of parameters defined as information elements (IEs) for aphysical random access channel (PRACH) operation of the WTRU; and aprocessor configured to process the received parameters to perform PRACHoperations, the IEs including PRACH system information, the PRACH systeminformation including a random access channel (RACH) response windowsize and PRACH frequency position information, the RACH response windowsize provided as a number of subframes, and one or more RACH responsessent to the WTRU being received by the WTRU over the RACH responsewindow.
 12. The WTRU of claim 11, wherein the PRACH system informationfurther includes PDCCH information and RA-RNTI information, the RA-RNTIinformation including at least one of the following parameters: aRA-RNTI code, a burst start sub-frame number or a next burst distance,and the PDCCH information including at least one of the followingparameters: a PDCCH format or a PDCCH scrambling code.
 13. The WTRU ofclaim 11, wherein the PRACH system information further includes at leastone of: PRACH burst type information, a channel coding parameter, or aPRACH frame structure parameter.
 14. The WTRU of claim 11, wherein theIEs include RACH non-dedicated preamble and signature information, theRACH non-dedicated preamble and signature information including at leastone of the following parameters: a number of signatures, a beginsignature index, or a signature map.
 15. The WTRU of claim 11, whereinthe IEs include RACH dedicated preamble and signature information, theRACH dedicated preamble and signature information including at least oneof the following parameters: a number of signatures or a begin signatureindex.
 16. An evolved NodeB (eNB), the eNB comprising: a processor, theprocessor configured to determine a plurality of parameters for physicalrandom access channel (PRACH) operations, the plurality of parametersincluding PRACH system information, the PRACH system informationincluding a random access channel (RACH) response window size and PRACHfrequency position information, the RACH response window size providedas a number of subframes, and one or more RACH responses sent from theeNB being received by a wireless transmit/receive unit (WTRU) over theRACH response window; and a transmitter, the transmitter configured totransmit the plurality of parameters defined as information elements(IEs) for a PRACH operation of the WTRU.
 17. The eNB of claim 16,wherein the PRACH system information further includes PDCCH informationand RA-RNTI information, the RA-RNTI information including at least oneof the following parameters: a RA-RNTI code, a burst start sub-framenumber or a next burst distance, and the PDCCH information including atleast one of the following parameters: a PDCCH format or a PDCCHscrambling code.
 18. The eNB of claim 16, wherein the PRACH systeminformation further includes at least one of: PRACH burst typeinformation, a channel coding parameter, or a PRACH frame structureparameter.
 19. The eNB of claim 16, wherein the IEs include RACHnon-dedicated preamble and signature information, the RACH non-dedicatedpreamble and signature information including at least one of thefollowing parameters: a number of signatures, a begin signature index,or a signature map.
 20. The eNB of claim 16, wherein the IEs includeRACH dedicated preamble and signature information, the RACH dedicatedpreamble and signature information including at least one of thefollowing parameters: a number of signatures or a begin signature index.